Temperature-operated signal



May 22, 1951 H. G. DUGAN TEMPERATURE OPERATED SIGNAL Filed Nov. 26, 1948 INVENTOR. Hugh 2 Shegis-Sheet 1 G.Du an H. G. DUGAN TEMPERATURE OPERATEQ SIGNAL May 22, 1951 I 2 Sheets-Sheet 2 Filed Nov. 26, 1948 INVENTOR. 7 Hugh 6. Dayan Patented May 22, 1951 2,553,814 TEMPERATURE-OPERATED SIGNAL Hugh G. Dugan, Hinsdale, Ill.

Application November 26, 1948, Serial No. 62,147

15 Claims. (01. 116-101) My invention relates to a signal which is primarily visual, and to the operating mechanism therefor which is motivated automatically in the presence of a predetermined temperature. One application for the present signal is in connection with a car wheel bearing, and the ensuing description will be confined thereto. In such an installation, if an excess of temperature develops, the signal will be operated to apprise the train crew, tower men, or other railroad employees, of a, dangerous condition that requires prompt remedial attention.

Certain suggestive embodiments of my invention are herein disclosed. In each of these the signal is operated through a pneumatic system with the indicating instrument located distantly from the point where operation of the signal is initiated. The signal mechanism utilizes a heatactuated explosive power means to impel a projectile; it may also include a second explosive power actuated by the first power means to, initiate operation of the signal. When two such power means are used, one in cooperation with the other, the one which is temperature-actuated to operate first will be referred to as primary, whereas the other which is actuated thereby will be referred to as secondary.

In the accompanying drawings, several suggestive embodiments of my invention are set forth in the manner following:

Figure 1 is a simplified diagrammatic representation of a railway train pneumatic system into which may be incorporated the present temperature-operated signal mechanism;

Fig. 2 is a top plan view, taken on line 2-2 of Fig. 3, showing one of the hoods in connection with the air line of a train signal or braking system, this hood mounting a frangible plate which is located directly over one of the power means;

Fig. 3 is an offset vertical section, taken on line 33 of Fig. 2;

Fig. 4 is an elevational view of a suggestive signal mechanism which may be connected with the train air line located distantly from the point where operation of the mechanism is initiated;

Fig. 5 is a detail in vertical section, taken on line 5-5 of Fig. 4;

Fig. 6 is a plan view of atpassenger car truck having roller bearings equipped with an air line system wherein is incorporated the present signal mechanism;

Fig. 7 is an enlarged detail in section, taken on line 1-1 of Fig. 6;

Fig. 3 is a fragmentary detail in longitudinal section showing application of a primary power housed within a journal box;

.9-9 of F g. 8;

means to a conventional bearing such as is usually Fig. 9 is a transverse section, taken on line Fig. 10 is an enlarged fragmentary detail in section, taken on line lll-l 0 of Fig. 8; Fig. 11, which is a view similar to Fig. '8, shows a modification'in the construction of the primary power means; and

Fig. 12 is an enlarged detail in section of an'- other form of power means which is adapted for use with the roller bearing of a passenger car.

The present signal apparatus in each of the forms shown may be applied to a standard car wheel bearing B enclosed within a journal box J at one end of a truck side frame 20 and which provided with an open front 2| normally closed by a hinged cover (not shown) and with side walls 22 (see Fig; 3). A primary power means P is carried by the bearing so as to be wholly enclosed by the journal box J. When installed on a plain bearing, as distinguished from a roller bearing, the primary power means P cooperates with a secondary power means S which is .dis-' posed exteriorly of the journal box. Since these several parts are common to the showings in most of the drawing figures, the same reference characters are applied thereto.

Referring particularly to Fig. 3, the secondary power means S comprises a vertically disposed hollow barrel 23 enclosed within a casing 24 which lies in spaced relation thereto. A fusee 25 may be coiled around within the annular space thus provided. A bushing 26 is screw threaded into the top of the journal box J and is also screw threaded into the base of the barrel 23 to secure the latter fixedly in place. The casing 24 is desirably inturned at its lower end to closely surround the bushing and underlie thebarrel, as shown. Secured to the top of the casing is a cap 28 having a central opening normally closed by a cap 21 of paper or the like which is affixed to its under face. Complete protection is thereby afforded to the barrel whose upper end lies closely adjacent the cap.

The bushing 26 is formed-interiorly with'a chamber 30 coaxial with the passageway in the. barrel for reception of the body 3| of a plunger 32 which extends downwardly through the bushing to carry at its lower end a head 33 whichis, exposed to the interior of the journal box. Extending upwardly from the plunger body is a fir'- ing pin 35 which underlies a cartridge 31 containing an explosive charge. Associated with the cartridge, to be operated thereby, is a projectile ing top a trail of smoke or smudge for visualsignal purposes.

The pellet 38 is expelled only when the cartridge 31 is discharged in response to operation of the firing pin. The firing pin, inturn, is dependent for its operation upon the presence of excessive temperature conditions Within the bearing B which mounts the primary power means P. As herein shown, the primary power means includes a barrel 50* (see Fig. 8') which upstands from one of the lugs i of the bearing B, and this barrel may, if desired, be equipped with radial fins 52 upon its exterior to facilitate the transfer of heat. This barrel at its lower end is reduced in external diameter to provide a neck 53 adapte'dto be screw threaded into a socket 54 which is extended into the bearing or hearing box from its upper face. A space is left between the bottom of this socket and the proximate end. of the barrel.

Internally the barrel is slightly enlarged in diameter in its neck region to provide a chamber 55 wherein, according to Fig. 8, is contained a bimetallic element 51 (see also Fig. 9) which normall remains coiled to a sufiiciently small diameter to underlie and support a cartridge 53 containing an explosive charge. Affixed to the cartridge bottom is a pad 59 of asbestos or other heat insulating material protected by an underlying disc 60 of metal or the like. The cartridge is maintained by the element 5'! at an elevation which is exteriorly of the chamber 55 so that it is not exposed directly to the temperature conditions therein prevailing. This is important because provision should be made to in- Sulate the explosive charge normally to an extent suih'cient to prevent its subjection to a wide normal temperature fluctuation. the event that an excess temperature should develop in the bearing', the bimetallic element which is directly exposed tosuch a condition will then expand circul'arly to the point of lying wholly outside the confines of the explosive charge thereabove which is then free to drop down into the chamber 55 to become quickly heated in consequence,

The upper end of the cartridge 58, when in its normally elevated position, lies somewhat below a ledge 6f whereon is rested a projectile in the form of a pellet adapted to be driven upward- Iy out of the barrel whenever the cartridge is ignited. This can take place only when the cartridge has'first dropped into the chamber 55, with the aid, if desired, of a spring 63' at the cartridge top, the force of the explosion therein being then directed upwardly to eject the pellet 62 in a like direction. Since the barrel 5!! from which the pellet is expelled is coaxial with the barrel 23 at the top of the journal box, the pellet 62 will be guided. through this short intervening distance to percuss the exposed head 33 whereby to operate the firing pin 35 tov cause ignition of the explosive cartridge 31 thereabove. When this takes place thepellet 38. is discharged from the upper barrel '23.

It will be noted that there is provided a primary and a secondary power means, arranged in tandem, so that the initiall discharged pellet will cause a discharge of the other pellet. Such an arrangement is advantageous largely because of (1) the enclosing journal box which intervenes between the bearing and the head 33 of the firing pin, and (2) the relative motion which is constantly taking. place between thebearing and its enclosing journal box when a railway car is in motion. The short distance traversed by the primary pellet 62 to set in operation the secondary pellet 38 will assure that the target, viz. the firing pin head 3'3, will be impacted. The explosive charge in the primary power means P is located close to the point where the excessive temperature originates, and so is affected sensitively by any such change. It may therefore be depended upon to operate for the purpose of operating the secondary power means S. The journal box which normally remainsclosed will afford full protection to the primary power means at all times. Mounting of the secondary power means in its casing 2'4 which is affixed to the top of the journal box, exteriorl thereof, assures a location for the discharged pellet 38 such that it will strike home to its intended target, as will now be explained.

At a point directly above each secondary power means is a hood 65 from which depends a sleeve 63 in screw threaded connection therewith as at Bl (see Fig. 3). Clamped between the skirt and sleeve is a frangible disc 68, desirabl convex downwardly, made of any suitable material such as thin metal, plastic, etc. This plate provides a seal across the mouth of the hood so as to prevent movement of air in or out. The hood is provided with a lateral extension 10, forming an inlet thereinto, and threaded for connection with a branch pipe H which is comprised in an air line system of the train provided either for-braking or signalling. A plug 72 is fitted within the extension 18 at a point close to the hood interior, and formed therethrough is a small opening 13 through which air may slowly pass to the atmosphere whenever the frangible disc 68 is broken.

Similar branch pipes, each in connection with a hood t5- and having a frangible sealing disc 68, are carried by each car 14, one being provided for each wheel bearing, so that any secondary pellet 38', if expelled from the secondary power means S as a result of an overheated condition in the associated wheel bearing, will operate to release air slowly from the brake system. As is usual, 2. train line pipe 75 is extended lengthwise of each ear to establish a closed pneumatic system lengthwise of the train, these train line pipes being suitably interconnected up to the locomotive cab where the usual controls are provided. As shown in Fig. l, a compressor 71 may be carried by the locomotive 18 to maintain a supply of air under pressure for operation of the car brakes or for other purposes.

In connection with the air system is a branch pipe (see Fig. 4) leading to a diaphragm or bellows 8| which is adapted to reciprocate a rod 82 having a laterally extended contact point 83 in operative relation to a fixed contact point 84 contained in an electrical circuit 85. A bell, lamp, or other electrically operated signal 86 is interposed in the circuit 85 which is in connection With a current source 0. By this arrangement an open circuit is provided when the normal air pressure is maintained in the pneumatic 75 system so that no signal will then be operated;

when this pressure drops below normal, however. the bellows 8| will produce endwise movement of the rod 82 to the point that the contacts 83 and 80 will be engaged, thereby closing the circuit and causing the electric signal system to be energized. An indicator of this character will at once apprise the engineer or other attendant on duty in the cab concerning a change in condition in the pneumatic system, and be recognized as a warning that a hot box has developed somewhere in the train of cars behind.

The indicating instrument of Fig. 4 may also comprise a bracket arm 90 whereon is pivotally mounted, at 9!, a bell crank having one arm 92 in connection at 93 with the reciprocable rod 82, and a second arm 94 which carries at its lower end a stylus 05 in operative relation to a slowly moving roll of paper 96 which is constantly advanced, as by a small motor (not shown), between two drums 37 and 98 while being unrolled from one and wound onto the other. This recording instrument is useful at all times to determine the operating characteristics of the brake system, and a graph line 39 which varies only normally from the straight may be relied upon to show that everything is functioning properly. On the other hand, if the pressure in the pneumatic system drops below normal, the bell crank will be rocked to the point of shifting the arm 94 beyond its usual operating range,

so that the resulting graph line I produced by the stylus 95 will move considerably to one side of normal and display a very different pattern. It is contemplated that release of air, whenever any one of the frangible discs 60 is broken, shall proceed slowly so that, if it be the brake system that is afi'ected, there will be no automatic setting of the brakes with consequent danger to the train. A little experience with the recording instrument, when operated in response to discerption of any of the sealing discs I58, will readily be interpreted as revealing the presence of a hot box somewhere in the train, the exact location being indicated by the smudge or smoke that is then being emitted from the secondary power means that has been operated.

A similar indicating instrument, involving an electrical signal and/or recording apparatus, may also be incorporated into the caboose end of a freight train. It will be subject to operation the same as the instrument, already described, when placed at the head end of the train. The crew members on duty in the caboose will then be apprised simultaneously with those on duty 'in the locomotive concerning the dangerous condition which requires attention. This provides a double assurance that the Warning signal will be heeded.

Certain modifications in the form and construction of the primary power means P also remain to be considered. In Fig. 11 the projectile-pellet I I2 is supported upon the ledge II I provided interiorly of the barrel I00, and therebelow is an explosive cartridge I08 supported above and out of a chamber I upon a thin walled tube I01 of low-temperature fusible metal chamber I05 where it is quickly raised to the ignition point so as to cause discharge of the pellet H2. The remainder of the operation is the same as already described.

In Fig. 12 I have shown a further modification in the construction of a power means which is suitable for either primary or secondary power purposes. I employ here a barrel I20 from which a projectile-pellet I2I is adapted for expulsion in an upward direction. The pellet in this construction rests directly upon the upper end of a cartridge I22 containing an explosive charge, the cartridge being supported upon the top wall I23 of a housing I24 to the top of which the barrel I20 is fixedly joined as by a screw threaded connection I25. Within the housing is an axial chamber I26 extending downwardly from the top wall I23 to an intermediate 7 cross wall I21. Mounted to reciprocate in this chamber is a plunger I30 which carries at its top a firing pin I 3| adapted, when advanced upwardly, to pass through an opening I32 in the top wall I23 to ignite the explosive charge in the cartridge I22. The plunger is supported by a coil spring I35 which is confined in place therebelow with its lower end resting on the transverse wall I21.

Depending from the plunger is a rod I37 which passes through the wall I2'I to carry on its lower end I38 a quartz bulb I 40 which is suspended therefrom by a connecting loop I lI of wire or the like. Such a bulb, usually made of quartz or glass. contains an expansible liquid which in the presence of a mounting temperature will produce disintegration of the bulb. This bulb lies within a bottom chamber I42 having opposite side walls I43 inclined inwardly to engage the proximate ends of the bulb whereby to prevent its being moved upwardly.

The housing I24 is shown as affixed to the top of the bearing box B where it is entered into a socket I45 and afiixed therein as by a screw threaded connection I46. The chamber I42 at the bottom of the housing is directly exposed to the heat of the bearing so as to be sensitively responsive to the temperature prevailing at that point. The quartz bulb which is located in this chamber will disintegrate whenever the bearing temperature exceeds a given point. When this takes place the rod I31 which theretofore was held down, against the tension of the spring I35, is released so that the spring will impel the plunger I30 upwardly to cause its firing pin I3I to ignite the explosive charge in the cartridge I22, thereby driving the pellet I2I upwardly and out of the barrel I20 to operate an associated secondary power means S (not shown) in the manner already explained. In this construction the quartz bulb may replace the explosive oartridge comprised in the primary power means P elsewhere described; when exploded it releases the spring I35 to furnish the power for operating the firing pin I3I whereby to ignite the cartridge I22 and send the pellet I2! on its way.

In Fig. 6 is shown the frame F of a passenger car truck equipped with roller bearings B. Carried by such a frame is a line of pipes I50 closed at opposite ends and in connection at I5I with the air signal system of the car. At a point over or opposite each wheel bearing the pipe line is outset to carry an interposed fitting I52 having a lateral outlet I53 to which is connected, as by screw threads, a hood I54. A frangible disc I55 of glass, plastic, metal or the like is secured in place between the outlet and hood to provide a seal against the escape of air from the pipe line.

[15.0 to the atmosphere. Opposite-the disc within the fitting may be; fixed a pad [55 to provide a cushion. stop for the pellet 36; 62', H2, or I'll, as the case may be, whenever the associated power means is operated in the manner hereinbefore explained.

Adjacent each fitting I52 the pipe line I 56 may carry a whistle I58: which is inoperative so long as; a pressure equilibrium exists upon opposite sides thereof; with breaking of any disc I55, air from within the pipe line is slowly vented into the atmosphere and in the presence of the unbalanced pressures: then obtaining on opposite sides of the proximate whistle, the latter is operated toproduce a sound which will be helpful in locating the point of trouble. Each whistle serves also-as a constriction in the pipe line to assure a slow escape of air therefrom whenever the proximate power means is operated, and this is a desirable end" for obvious reasons.

It will be understood that the location of the several hoods I54, and the directions in which they are faced, will depend to some extent on the journal box and truck design. In each such installation, however, there need be but a single power means P, mounted on the wheel bearing B and operable in response to temperature thereof exceeding a predetermined point to project a pellet outwardly to strike and break the disc I55 whereby to release air from the pipe line I50 to operate one or more signals in the associated pneumatic system, as already explained at length.

The signal apparatus in each of the forms thus far described is characterized by a pneumatic system of indefinite length which interconnects the signalling instrument or instruments with the primary and secondary power means at the point of temperature origin which must be safeguarded.

It will be noted that in each of the forms of the mechanism herein described, use is made of a projectile to. be discharged through an air gap for actuation of the signal mechanism. Becauseof the, conditions existing within ajournal. box, it is very unsatisfactory to attempt any physical connection, mechanical, electrical, or otherwise, between the bearing and the parts exteriorly thereof. This is due to the constant relative movement of the bearing and, the journal box, resulting from advance of the car wheels over the rails. By leaving an air gap across which the projectile is shot to set in motion the signal apparatus, the difficulties of a physical connection are avoided. It will be noted that the signal may include devices at one or both ends of a train far removed from the danger point where the duplex power means has been operated, or it may comprise one or more signal devices on each car, each such device being connected for opera tion. with any one of the several duplex power means.

In the case of a wheel which is journaled in an anti-friction bearing, the cartridge may conveniently be mounted on the inner side of the journal box so as to be sensitive to an increase of'temperature therewithin. While the box temperature may not be as hot as the bearing itself, it does attain to a higher temperature, in case of overheating, than the outside atmosphere, consequently a cartridge which is mounted within the box will be fully effective.

The subject matter of the present invention was, in part, disclosed in my application Serial No. 667,548, filed May-6, 1946, and now abandoned.

I claim:

1. A railway train signal systemcomprisingan inter-car air. pressure line. and, in connection therewith, a pneumatically-operated signal, a plurality of temperature-actuated primary power means, one mounted on each car wheel bearing, a secondary power means associated with each primary power means. and arranged to be. set in operation thereby, and normally closed venting means in the air line in operative relation with each secondary power means adapted, in response to operation thereof, to be opened for release of air whereby to cause operation of the signal.

2. A railway train signal system comprising an inter-car air pressure line and, in connection therewith, a pneumatically-operated signal, a plurality of temperature-actuated primary power means, one mounted on each car wheel bearing, a plurality of normally closed frangible means for venting the air line, a secondary power means associated with each frangible venting means and with each primary power means and arranged to be set in operation by the latter, the secondary power means including a projectile fixedly aimed at one of the frangible venting means and adapted, upon discharge, to break the same whereby to cause operation of the signal.

3. A signal device in which is comprised a. temperature-actuated explosive means together with a releasable projectile adapted to be discharged thereby in a fixed direction and, spaced,

therefrom and opposite thereto, a secondary power means arranged for operation by the projectile when discharged from the explosive means; and motion-transmitting means set in operation by the secondary power means, when operated,

for operating a signal.

i. A signal device in, which is comprised a temperature-actuated explosive means together with a projectile adapted to be discharged thereby and, spaced therefrom and opposite thereto, a secondary power means arranged for operation by the projectile when discharged from the explosive means, motion-transmitting means set in operation by the secondary power means, whenoperated, a fusee projectible to a forward position in response to operation of the secondary power means, and means, for automatically igniting the fusee when forwardly projected.

5; A temperature-operated signal, for a journal-enclosed bearing, comprising an explosive cartridge carried by the bearing and subject to the temperature thereof, a projectile carried by the cartridge for discharge therefrom when explosion takes place, a casing carried by a wall of the journal exteriorly thereof, a plunger mounted for reciprocation within the casing having one end within the journal opposite the projectile and adapted to be operated thereby when the projectile is discharged from the cartridge, a second explosive cartridge associated with the plunger and adapted to be operated upon movement thereof, and signalling means in operative relation to the second explosive cartridge and arranged, upon operation thereof, to be operated thereby.

6. A temperature-operated signal for a bearing enclosed within a journal box, comprising a primary power cartridge, including a projectile, carried by the bearing and subject to the temperature thereof, a casing carried by the journal box exteriorly thereof, means within the cartridge actuated by an excess of bearing temperature for discharging the projectile therefrom, a plungermounted for reciprocation within the casing havupon operation of the power means, to be discharged outwardly therefrom, and, mounted on the journal box but exposed upon the interior thereof in the path of travel of the discharged projectile, a signal-operating secondary power means arranged for operation when impacted by the projectile following its discharge from the primary power means.

8. For use with a railway car journal box through which is an opening, a barrel secured to the box opposite the opening, an explosive cartridge within the barrel having an associated signal-operating projectile adapted to be discharged outwardly therefrom upon explosion of the cartridge, a firing pin movable axially of the barrel for igniting the cartridge, the firing pin having a portion of itself extended through the opening to lie interiorly of the box, and temperature-operated power means secured to the bearing adapted in response to an excess of temperature to percuss the firing pin whereby to ignite the cartridge and discharge the signal-operating projectile.

9. For use with a railway car journal box through which is an opening, a barrel secured to the box opposite the opening, an explosive cartridge within the barrel having an associated signal-operating projectile adapted to be discharged outwardly therefrom upon explosion of the cartridge, a firing pin movable axially of the barrel for igniting the cartridge, the firing pin having a portion of itself extended through the opening to lie interiorly of the box, temperatureoperated power means secured to the bearing adapted in response to an excess of temperature to percuss the firing pin whereby to ignite the cartridge and discharge the signal-operating projectile, and a fusee arranged exteriorly of the barrel adapted for ignition by the cartridge, when exploded, whereby to give off a visual signal.

10. A railway train signal system comprising an inter-car air pressure line and, in connection therewith, a pneumatically-operated signal, frangible venting means for the air line, a plurality of upstanding barrels mounted on the car wheel bearings, a cartridge containing a temperature-actuated explosive means positioned within each barrel and adapted, upon ignition, to break the frangible venting means whereby to cause operation of the signal, and a temperature-released support for each cartridge adapted to maintain the same normally in a relatively cool elevated position within the barrel but to permit gravity dropping of the cartridge in response to mounting bearing temperatures beyond a predetermined point.

11. A railway train signal system comprising an inter-car air pressure line and, in connection therewith, a pneumatically-operated signal, a normally closed frangible means for venting the air line, temperature-actuated explosive means carried by one of the car wheel bearings, subject to the temperature thereof, and positioned proximate to the frangible venting means, and a projectile associated with the explosive means and arranged, upon discharge thereof, to cause breaking of the frangible venting means to produce operation of the signal.

12. For use with a railway car wheel bearing wherein is a socket, a barrel having one end portion fixedly secured within the socket and formed at its inner end with a chamber opposite the socket, a heat explosive cartridge positioned within the barrel in a relatively cool portion thereof outwardly beyond the chamber, means for holding the cartridge outwardly beyond the chamber, but releasable at a predetermined temperature therein to permit movement of the cartridge into the chamber whereby to subject the cartridge to an explosive temperature therewithin, and a projectile within the barrel arranged to be discharged therefrom upon explosion of the cartridge.

13. For use with a railway car wheel bearing wherein is a socket, a barrel having one end portion fixedly secured within the socket and formed at its inner end with a chamber opposite the socket, a heat explosive cartridge positioned within the barrel in a relatively cool portion thereof outwardly beyond the chamber, means for holding the cartridge outwardly beyond the chamber, but releasable at a predetermined temperature therein to permit movement of the cartridge into the chamber whereby to subject the cartridge to an explosive temperature therewithin, a projectile within the barrel spaced from the cartridge and arranged to be discharged from the barrel upon explosion of the cartridge therewithin, and means for holding the projectile in a fixed position outwardly of the chamber of the barrel prior to discharge therefrom.

14. For use with a railway car wheel bearing wherein is a socket, a barrel having one end portion fixedly secured within the socket and formed at its inner end with a chamber opposite the socket, a heat explosive cartridge positioned within the barrel in a relatively cool portion thereof outwardly beyond the chamber, heat insulating means normally protecting the cartridge from the temperature conditions within the enlarged chamber, means for holding the cartridge outwardly beyond the chamber, but releasable at a predetermined temperature therein to permit movement of the cartridge into the chamber whereby to subject the cartridge to an explosive temperature therewithin, and a projectile within the barrel arranged to be discharged therefrom upon explosion of the cartridge.

15. A signal system for railway car wheels comprising a plurality of barrels one mounted on each wheel bearing, a projectile arranged for discharge outwardly from the barrel, temperature-actuated explosive means positioned within each barrel and adapted, upon ignition, to expel the projectile therefrom, a frangible means opposite each barrel in position to be impacted by the projectile, when discharged therefrom, to be broken thereby, a signal common to a plurality of frangible means comprised in a single system, and normally-restrained self-operating means for the signal in connection with all frangible means in the same system and releasable for operation in response to breaking of any one of said frangible means.

HUGH G. DUGAN.

No references cited. 

